Approximately one-third of HIV-1 infected individuals develop HIV-1-associated neurocognitive disorders (HAND). Symptoms range from minor difficulties to severe neurodegenerative dementia and even with the advent of highly active antiretroviral therapy (HAART), while severe HIV-associated dementia is less common, minor cognitive motor disorders remains an important part of infection. The deleterious effects of opiates are complex and information regarding the actions of drugs of abuse on glial cell function is very limited though they are known to be critical to opiate response. Moreover, the consequent effects of the actions of drugs of abuse and the manifestation of substance abuse on neuronal function are not well known. The proposed project will investigate the role of autophagy in microglia-induced neuroAIDS in the context of substance abuse. The three correlated specific aims are directed at: 1) identifying a novel mechanism in the biology of microglia that regulates HIV-1 replication and whether morphine converges on HIV-1 infection through this pathway~ 2) characterization at cellular levels the consequences of HIV-1 induced lysosomal dysfunction and whether prior and/ or concurrent substance abuse modifies cell function~ 3) examining the signaling pathways and the significance (protective vs. toxic) of the autophagy process activated by HIV-1 and morphine in microglia cells and neurons. Dr. El-Hage has the expertise, leadership, and motivation necessary to run a successful research program and the purpose of getting this award is to enable Dr. El-Hage to become an independent scientist.